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Journal of Earth Science 2018年第1期29卷 30-42页

作者： Haijin Xu junfeng zhang State Key Laboratory of Geological Processes and Mineral Resources School of Earth SciencesChina University of Geosciences

The plate affiliation of the North Dabie terrane （NDT） has been controversial. To address this fundamental question, an integrated study of internal structure, in-situ U-Pb dating and trace element analysis in zircons and field investigation for migmatite in the NDT was carried out, which reveals par- ticipation of crustal rocks of the North China Craton （NCC） in the protolith in addition to the more common crustal rocks of the Yangtze Craton （YC）. The evidence of an NCC affinity for protolith of migmatite in the NDT is the -2.5 Ga （2 486±14 and 2 406±26 Ma） magamtic age and -1.8 Ga （1 717±79 Ma） metamorphic age in the relict zircon domains because these two age groups are characteristic for the evolution of the NCC. The evidence of a YC affinity for protolith of migmatite in the NDT is the more common 0.7-0.8 Ga （e.g., 787±12 Ma） magamtic zircon age. Mid-Neoproterozoic magmatic age （0.7-0.8 Ga） is a symbol of YC basement rocks. In view of the widely exposed YC crustal components in the NDT, we suggest that the protolith of the NDT is mainly crustal rocks from the YC with minor crustal components from the NCC. The zircon rim domains and new growth grains from all the migmatite sam- ples are characterized by anatectic zircons and have a widely concordant ages ranging from 112.2±2.8 to 159.6±4.3 Ma with several peak values, suggesting a long lasting multistage anatexis. In conclusion, the NDT has a mixed protolith origin of both the YC and the NCC crustal rocks were strongly remoulded by anatexis during orogenic collapse.

关键词： North Dabie terrane migmatite zircon U-Pb age protolith tectonic affinity.

基于GIS的青岛市绿地景观生态格局与网络构建

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中国海洋大学学报（自然科学版） 2024年第8期54卷 103-112页

作者：鲁敏孙速速张晴晴张俊峰郭晓伟高鑫山东建筑大学风景园林科学研究中心山东济南250101

定量化研究绿地景观生态格局和网络构建能够为城市绿地系统和国土空间的科学规划提供理论依据与方法支撑。研究基于无线电高空测候(RS)和地理信息系统(GIS)技术,运用总体景观生态格局分析和梯度分析方法,选取12个景观指数,对沿海城市—... 详细信息

定量化研究绿地景观生态格局和网络构建能够为城市绿地系统和国土空间的科学规划提供理论依据与方法支撑。研究基于无线电高空测候(RS)和地理信息系统(GIS)技术,运用总体景观生态格局分析和梯度分析方法,选取12个景观指数,对沿海城市——青岛市的绿地景观生态格局从斑块类型水平和景观水平两方面进行了定量研究。结果表明:斑块类型水平上,区域绿地以大型斑块为主且占优势地位,防护绿地以大中型斑块为主,二者虽空间分布不均匀,但生态效益较好;附属绿地以中小型斑块为主,缺乏大面积绿地建设,景观破碎度高但符合公众游憩需求;公园绿地以小型斑块为主且数量较少,在城区集中分布。景观水平上,城市绿地景观类型较齐全,但整体破碎度高,中部地区景观破碎度高,南部与中北部地区绿地类型多样,景观破碎度高且景观形状较复杂。在此基础上,进而分析了青岛城市绿地景观生态格局存在的问题,提出了“一轴、三核、廊汇成网、节点密布”的城市绿地生态网络优化与构建方案,以提高各类城市绿地连接度水平,发挥绿地生态系统的整体效益。

关键词：地理信息系统(GIS) 城市绿地景观生态格局梯度分析生态网络构建

数字经济对体育用品制造企业创新绩效的影响研究

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山东体育学院学报 2024年第2期40卷 47-58,78页

作者：秦丹欧阳喜玉张俊峰邢学峰首都体育学院管理与传播学院北京100191 北京开放大学科学技术学院北京100081

数字经济能够提升企业创新绩效赋能体育制造业高质量发展,推进我国从“制造大国”迈向“智造强国”。该研究基于2011—2021年我国省(区、市)数字经济数据与沪深A股体育用品制造业上市企业数据,探究了数字经济对企业创新绩效的微观影响... 详细信息

数字经济能够提升企业创新绩效赋能体育制造业高质量发展,推进我国从“制造大国”迈向“智造强国”。该研究基于2011—2021年我国省(区、市)数字经济数据与沪深A股体育用品制造业上市企业数据,探究了数字经济对企业创新绩效的微观影响及作用机制。影响结果表明,数字经济能显著提升体育用品制造企业创新绩效,这一结论在经过一系列的稳健性检验后依然成立;作用机制结果表明,数字经济可通过人力资本优化、商业模式创新两种方式提升体育用品制造企业创新绩效;异质性分析表明,数字经济对资本密集型企业、技术密集型企业和劳动密集型企业创新绩效均有正向显著影响,影响效果呈现依次递减的梯度布局。针对上述结果,该研究提出了以下建议:强化数字经济发展思维,加强数字经济与体育用品制造企业融合发展;企业应加大对高技能人力资本的培育和引进,加强员工数字技能的培训和提升;企业应重视商业模式创新,为实现企业长效创新机制提供助力;立足不同企业自身要素特点,“因企而宜”地推进数字经济对其创新发展的影响策略。

关键词：数字经济体育用品制造企业创新绩效人力资本商业模式创新

Incremental support vector machine algorithm based on multi-kernel learning

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Journal of Systems Engineering and Electronics 2011年第4期22卷 702-706页

作者： Zhiyu Li junfeng zhang Shousong Hu Research Institute of Unmanned Aircraft Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China College of Civil Aviation Nanjing University of Aeronautics and Astronautics Nanjing 210016 R R. China College of Automation Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China

A new incremental support vector machine （SVM） algorithm is proposed which is based on multiple kernel learning. Through introducing multiple kernel learning into the SVM incremental learning, large scale data set learning problem can be solved effectively. Furthermore, different punishments are adopted in allusion to the training subset and the acquired support vectors, which may help to improve the performance of SVM. Simulation results indicate that the proposed algorithm can not only solve the model selection problem in SVM incremental learning, but also improve the classification or prediction precision.

关键词： support vector machine (SVM) incremental learning,multiple kernel learning (MKL).

Selective catalytic oxidation of NO over iron and manganese oxides supported on mesoporous silica

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Journal of Natural Gas Chemistry 2008年第3期17卷 273-277页

作者： junfeng zhang Yan Huang Xia Chen Department of Environmental Science and Engineering Xiangtan University Xiangtan 411105 Hunan China

The selective catalytic oxidation （SCO） of NO was studied on a catalyst consisting of iron-manganese oxide supported on mesoporous silica （MPS） with different Mn/Fe ratios. Effects of the amount of manganese and iron, oxygen, and calcination temperature on NO conversion were also investigated. It was found that the Mn-Fe/MPS catalyst with a Mn/Fe molar ratio of 1 showed the highest activity at the calcination temperature of 400 °C. The results showed that over this catalyst, NO conversion reached 70% under the condition of 280 °C and a space velocity of 5000 h-1. SO2 and H2O had no adverse impact on the reaction activity when the SCO reaction temperature was above 240 °C. In addition, the SCO activity was suppressed gradually in the presence of SO2 and H2O below 240 °C, and such an effect was reversible after heating treatment.

关键词： selective catalytic oxidation of NO nitrogen monoxide mesoporous silica iron manganese

Effects of Water on the Rheology of Dominant Minerals and Rocks in the Continental Lower Crust: A Review

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Journal of Earth Science 2020年第6期31卷 1170-1182页

作者： Zhonghang Wang Feng Shi junfeng zhang State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430078China School of Earth Sciences China University of GeosciencesWuhan 430074China

As an important part of the continental lithosphere, the continental lower crust can influence and control many important geodynamic processes, which are of great significance to the evolution of the lithosphere. Extensive plastic deformation is common in continental lower crust. There have been many studies focusing on the rheology of the continental lower crust in the past few decades. This paper provides a review on the effects of water on the rheology of dominant minerals(clinopyroxene, plagioclase and garnet) and rocks in the continental lower crust. The water contents in continental lower crustal minerals and rocks are in general rich and very heterogenous from sample to sample and region to region. Water can significantly reduce the strength of clinopyroxene, plagioclase, garnet and lower crustal rocks. Water can also have a profound influence on fabric development and slip systems in lower crustal minerals. Quantitative experimental investigations and extensive natural studies of water effect on rheology are necessary to refine the classic lithosphere strength profile models and to address the existing controversy on strength of the continental lower crust.

关键词： continental lower crust water content rheology fabric slip system

Magnetic Fabric and Petrofabric of Amphibolites from the Namcha Barwa Complex, Eastern Himalaya

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Journal of Earth Science 2020年第1期31卷 115-125页

作者： Wenjing Li Haijun Xu junfeng zhang Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences、Wuhan 430074China School of Earth Sciences China University of GeosciencesWuhan 430074China

The magnetic fabric and petrofabric are often used as tectonic indicators of geological and geodynamic processes that a rock has experienced such as growth, deformation and metamorphism. This study presents the low field anisotropy of magnetic susceptibility(AMS) and the crystallographic preferred orientation(CPO) of constituent minerals in amphibolites from the Namcha Barwa Complex in the eastern Himalayan Syntaxis, Tibet. The bulk magnetic susceptibility varies significantly from 7.3×10^(-4) to 3.314×10^(-2) SI, with the Jelínek's anisotropy values(Pj) ranges from 1.094 to 1.487. The maximum susceptibility is approximately parallel to the lineation while the minimum susceptibility is subnormal to the foliation plane. Electron backscatter diffraction(EBSD) analyses show pronounced CPOs of amphibole in all samples, with a preferred alignment of the [001] axes along the lineation and the [100] axes spreading along a girdle normal to the lineation. Numerical simulations and comparison with laboratory measurements suggest that the magnetic anisotropy of amphibolite is largely controlled by the CPOs of amphibole. If present, the well oriented iron-titanium oxides such as ilmenite along rock foliation and lineation could increase the susceptibility and the anisotropy of a rock. Our results show a strong correlation between the magnetic anisotropy and the petrofabric of amphibolite, which could provide constraint for the interpretation of strong magnetic anomalies observed in the tectonic syntaxes of Tibet.

关键词： petrofabric anisotropy of magnetic susceptibility crystallographic preferred orientation amphibolite Tibet

Security control of positive semi-Markovian jump systems with actuator faults

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Control Theory and Technology 2021年第2期19卷 197-210页

作者： junfeng zhang Haoyue Yang Suhuan zhang Xianglei Jia School of Automation Hangzhou Dianzi UniversityHangzhou310018ZhejiangChina

Actuator faults usually cause security problem in *** paper is concerned with the security control of positive semi-Markovian jump systems with actuator *** considered systems are with mode transition-dependent sojourn-time distributions,which may also lead to actuator ***,the time-varying and bounded transition rate that satisfies the mode transition-dependent sojourn-time distribution is ***,a stochastic co-positive Lyapunov function is *** matrix decomposition technique,a set of state-feedback controllers for positive semi-Markovian jump systems with actuator faults are designed in terms of linear *** the designed controllers,stochastic stabilization of the systems with actuator faults are achieved and the security of the systems can be ***,the proposed results are extended to positive semi-Markovian jump systems with interval and polytopic *** virtue of a segmentation technique of the transition rates,a less conservative security control design is also ***,numerical examples are provided to demonstrate the validity of the presented results.

关键词： Positive semi-Markovian jump systems Sojourn-time distribution Actuator faults Linear programming

Event-Triggered L1-Gain Control of Nonlinear Positive Switched Systems

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Journal of Systems Science & Complexity 2021年第3期34卷 873-898页

作者： zhang junfeng LIU Laiyou LI Shuo DENG Xuanjin School of Automation Hangzhou Dianzi UniversityHangzhou 310018China Inria University of LilleCNRSUMR9189-CRIStALF-59000 LilleFrance

This paper is concerned with the event-triggered L1-gain control of a class of nonlinear positive switched ***,an event-triggering condition in the form of 1-norm is presented for the *** virtue of the event-triggering strategy,the original system is transformed into an interval uncertain *** event-triggered L1-gain controller is designed by decomposing the controller gain matrix into the sum of nonnegative and non-positive *** the design controller,the resulting closed-loop systems are positive and L1-gain *** obtained approach is developed for the systems subject to input *** presented conditions are solvable in terms of linear ***,two examples are provided to verify the effectiveness of the design.

关键词： Event-triggered control input saturation linear programming nonlinear positive switched systems

国产数据库在能源数字化转型中的创新应用研究

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信息通信技术与政策 2024年第10期50卷 68-74页

作者：董文张俊峰刘俊张雷中电科金仓(北京)科技股份有限公司北京100085 中国信息通信研究院技术与标准研究所北京100191

在全球能源格局重塑与国内能源化工行业转型升级的大背景下,数字化转型已成为能源行业提升竞争力的必由之路。深入探讨了异构数据库智能迁移、数据库自治优化及灵活扩展体系架构等创新技术,有效破解了数据库迁移难题,提升了数据处理效... 详细信息

在全球能源格局重塑与国内能源化工行业转型升级的大背景下,数字化转型已成为能源行业提升竞争力的必由之路。深入探讨了异构数据库智能迁移、数据库自治优化及灵活扩展体系架构等创新技术,有效破解了数据库迁移难题,提升了数据处理效能与系统稳定性。国产数据库凭借其多模数据处理与云数据库技术,为石油石化行业构筑了强大的数据管理与服务能力,有力推动了行业数据共享、业务协同与运营效率的全面提升。该能源企业上游开发生产系统整合上云升级项目的成功实践,充分验证了国产数据库在实际应用中的良好表现,展现了其在能源行业数字化转型中的巨大潜力与价值。

关键词：能源数字化转型国产数据库自治优化多模数据云数据库

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